A362128 Indices of records in A360179.

1, 3, 5, 7, 9, 12, 15, 21, 25, 29, 52, 69, 87, 100, 138, 176, 233, 252, 265, 338, 371, 384, 400, 447, 459, 492, 515, 594, 606, 677, 779, 794, 850, 896, 1100, 1144, 1204, 1225, 1243, 1584, 1674, 1700, 2214, 2239, 2265, 2338, 2568, 3014, 3621, 3652, 4027, 4058, 4437, 4464, 4584, 4625, 5111, 5201, 5281

Offset: 1

Author

Michael De Vlieger, Apr 09 2023

Keywords

• nonn

Links

• Michael De Vlieger, Table of n, a(n) for n = 1..8238

Crossrefs

Cf. A000005, A360179, A362127.

Programs

Mathematica

nn = 6000; c[] := False; h[] := 0; f[n_] := DivisorSigma[0, n];
a[1] = j = u = 1; r = 0;
{1}~Join~Rest@ Reap[Do[
      If[c[j],
        k = j + f[u]; h[j]++; h[u]--,
        k = f[j]; c[j] = True; h[j]++ ];
      u = Min[u, j]; Set[{a[n], j}, {k, k}]; While[h[u] == 0, u++];
      If[k > r, r = k; Sow[n]], {n, 2, nn}] ][[-1, -1]]